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Why Does My Bathroom Smell Like Sewage? 6 Possible Reasons

bathroom interior design

Bathrooms aren’t the cleanest places to begin with, which is why regular cleaning and air fresheners are recommended. However, when your otherwise clean bathroom starts to smell like sewage, alarm bells start to go off. Let’s take a look at some reasons your bathroom smells like sewage and what to do about it.

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The 6 Reasons Why Your Bathroom Smells Like Sewage

1. The Shower Is Clogged

Our bodies naturally shed some hair in the shower, and many people shave there, too. If hair gets into the drain, it can clog up along the way and ferment. Other things that can get into the drain are dead skin cells, soap, gels, and other debris. Together, they can build up and produce smells similar to sewage.

To remedy this situation, combine a half cup of white vinegar with a half cup of hot water. Unscrew your shower drain cover and pour this solution down the drain, then pour in a cup of baking soda afterward. Allow this to sit for a couple of hours and use a long-handled brush to scrub away debris in the pipe. In most cases, this treatment will fix the issue. If not, you might have to take a new plan of action.

tiled shower with drain
Image Credit: Brilliant Eye, Shutterstock

2. Damaged Toilet Seals

Your toilet has wax seals that prevent water and sewage gas from bubbling up into your toilet, but when these rings are damaged or broken, you can smell or see sewage in the bathroom. To fix this problem, have a professional plumber install new wax seals on your toilet. The wax seals are relatively cheap, so you really only have to pay for the time it takes for the plumber to install a new one.

3. Broken or Clogged Vent Pipe

plumber tools and equipment in a bathroom, plumbing repair service
Image Credit: amedeoemaja, Shutterstoock

Toilets have a special pipe called a vent pipe, which helps flush the system of water, debris, and sewage. When the pipe is clogged or broken, sewage can bubble up into your toilet, shower, or sink. Possible causes of a broken or clogged vent pipe include solid objects obstructing the vent pipe and poor installation that caused the pipe to fail or develop cracks.

We recommend calling a professional to check the pipe for any blockages or damage. They’ll be able to remove any blockages and replace the pipe if necessary.

4. Bacteria

Human hair and other debris that finds its way into your drains can build up and ferment, which attracts bacteria. When they feast and reproduce, these bacteria can produce a sewage-like odor that emanates throughout your bathroom. This problem is especially common during the hot summer months.

To get rid of smelly bacteria in your bathroom, use a bleach flush. For your toilet, add a cup of bleach to the tank and flush it several times. For your other drains, mix a half cup of bleach and a half cup of water and pour directly down the drains. Bleach is one of the most effective ways to kill harmful bacteria. However, you should be sure to open the windows and keep the area well-ventilated so that you don’t breathe in any harsh chemicals. Consider wearing rubber gloves as well to protect from chemical burns.

5. Sewer Backup After Rain

After heavy rainfall, your city’s sewage system can get overwhelmed. Excess runoff water puts pressure on septic systems and can make sewage bubble up into your sink, toilet, and shower. Sometimes, liquid sewage bubbles up, and other times only gas does. There’s very little you can do about this problem, but the good news is that it will resolve on its own in a day or two. If the problem continues, it is best to call a plumber.

A working plumber opens a sewer hatch (cesspool)
Image Credit: Natalia Kokhanova, Shutterstock

6. Your Septic Tank Is Full

Septic tanks normally drain on their own, but sometimes you need to manually drain them. If the tank gets too full, sewage will backflow into your pipes and come up through the drains. It starts with a foul odor and quickly graduates into full blown sewage. Immediately drain your septic tank if you suspect that’s your culprit.

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Everyone loves a clean bathroom, but sewage smells can ruin the room’s whole atmosphere. Plus, who wants to smell foul sewage in their home? There are numerous reasons sewage smells occur, but they’re usually fixed with a call to a local plumber or by homemade cleaning remedies.

Featured Image Credit: Beyond Time, Shutterstock


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